480 206. LABIATAE 



64. Corolla two-lipped ; upper lip notched or 2-cleft, lower 3-cleft. Stamens 



4, in two pairs of more or less unequal length. [Subtribe thymin ae.] 65 



Corolla equally or subequally 4-cleft ; tube included. Stamens 4, about 



equal in length, with parallel halves, rarely only 2. Herbs. [Subtribe 



MENTHINAE.] 69 



65. Calyx more or less distinctly 2-lipped. Leaves entire 66 



Calyx equally 5-toothed 68 



66. Upper lip of the calyx entire or obscurely 3-toothed ; lower lip slightly 2- 



toothed, almost entire, or rudimentary. Anther-halves spreading. Herbs. 

 Bracts suborbicular. — Species i (M. hortensis Moench). Cultivated 

 and sometimes naturalized in North Africa. Used as a pot-herb, for 

 the preparation of an essential oil and a kind of snuff, and in medicine. 

 " Marjoram." (Under Origanum L.) . . . . Majorana Moench 

 Upper lip of the calyx 3-toothed, lower 2-cleft 67 



67. Calyx-tube much compressed from above, 13-nerved. Corolla pink ; 



tube exserted ; upper lip 2-cleft. Anthers with a small connective and 

 spreading halves. Style-apex unequally 2-cleft. Shrubs. False whorls 

 6-flowered, in heads. — Species i. North Africa. (Under Thymus L.) 



Coridothymus Reichb. fU. 

 Calyx-tube more or less cyHndric, not or slightly compressed. Anthers with 

 a thick connective. Style-apex equally or subequally 2-cleft. — 

 Species 20. North Africa and Abyssinia. Some species yield condi- 

 ments, medicaments, and an essential oil, or serve as ornamental plants. 

 " Thyme." Thymus L. 



68. Corolla-tube more or less projecting beyond the calyx. Anthers exserted, 



with spreading halves. Style-apex unequally 2-cleft. Herbs. — 

 Species 5. North Africa. They yield condiments, medicaments, and an 



essential oil Origanum L. 



Corolla-tube not projecting beyond the calyx. Anthers with parallel halves. 

 Shrubs. — Species 9. Madeira and Canary Islands. Bystropogon L'Her. 



69. Stamens 2. Anther-halves finally spreading. Calyx equally 5-toothed, 



glabrous within. Nutlets truncate at the apex. Leaves toothed. 

 False whorls many-flowered, axillary. Bracteoles small. — Species i. 



North Africa. Used medicinally Lycopus L. 



Stamens 4. Nutlets round at the apex 70^ 



70. Calyx equally 4-toothed, hairy within ; teeth with an awn-like process 



on the back. Stem decumbent. Leaves linear. False whorls axillary, 

 many-flowered. Bracteoles large, as long as the flowers. — Species i. 



North-West Africa. Used medicinally Preslia Opiz 



Calyx equally or subequally 5-toothed ; teeth without an awn-like process 

 on the back. Bracteoles small. — Species 9. North Africa, northern 

 Central Africa, and South Africa, also naturalized in Madagascar, its 

 neighbouring islands, and St. Helena. Some species (especially M. 

 piperita L., peppermint) yield condiments, medicaments, insectifuges, 

 and an essential oil used as an aromatic or for medicinal purposes ; 

 several serve as ornamental plants. " Mint." . . . Mentha L. 



